Cleaning composition and method for its use



252 COMPOSlTlONS.

Patented Aug. 17, 1943 Cross Reference 2326,837 CLEANINGVCOMPOSITION AND METHOD ronrrsusn Timothy J. Coleman, Bufialo, N. '17.; assignor to National Carbon Oompa of New York Inc., a corporation f N Drawing. Application ,Tanuary l3, 1940,

Serial No. 313,721 a 10 Claims. (cuss-+1 42) This invention relates to the cleaning of metal surfaces; and to a composition and method for 'its' use that is'particularly adapted for removing scale, rust, and other oxide formations, and deposits or films of grease and oil, from the surfaces of heat-exchange equipment, such -as the cooling systems of internal combustion engines. I The composition of the invention has especial utility for the removal of scale; rust, oil' and grease deposits, etc. from the heat-exchange surfaces of present-day internal combustion engines, portions of which surfaces are formed of aluminum, brass, copper, tin, solder, and other non-ferrous metals subject to ready attack by acidic reagents in aqueous solutionpj V It is well known that considerable corrosion normally occurs in the cooling systems'of internal combustion enginesv even when'wate'r alone is used as the cooling agent. This corrosion is often intensified when certain types of antifreeze compounds are used in such systems; so that the radiator tubes become more or less clogged with scale and rust. Grease and oil which may enter the cooling fluid at the circulation pump deposit on the radiator tubes and other parts and he'lp to bond these solids thereto.-

Many preparations for periodically, removing these undesirable. deposits from cooling systems have been tried. Many of 'the'm are alkaline, and usually contain caustic alkalies', sodium carbonate, tri-sodium phosphate, or sodium silicate Y The advent. of aluminum cylinder heads has rendered such alkaline cleaning compounds objectionable because 'of the rapid attack of aluminum by alkalinesolutions. Furthermore, where organic antifreeze compounds are used, the presence of even small amounts of alkaline silicates causes the formation of an insoluble gel which increases the radiator clogging efiect. Such cleaners have no action upon rust coatings or. upon rust itself; nor have theypowers, of loosening iron oxide scale from the metal.

Acidcleaning compositions are extremely'ef fective for removing oxide scale; However, the I common acids readily attack'aluminum a'sv well as iron, brass, copper, and various other metals used in heat-exchange apparatus. Moreover, 'the usual acid compositionsare not capable of removing grease and oil present upon the metal surfaces.

,The present invention is based in important part upon the discovery that by the, employment of certain mixtures of solid compounds, hereinafter more fully dgscribed stable-acidic cleaning composition may be produced which, insolution in water or other solvent,- is highly efiective for removing from a: heat-exchange system rust, scale, and other solid impurities, together with grease and oil, while preventing or inhibiting undesirable attack by the acidic components upon parts of the system made of such. non-ferrous n etalsas aluminum, brass, copper,.tin and lead.

- Among the more-important objects of the in-- vention are: To provide a novel composition and method adapted to remove scale, rust, grease, oils and the like-from metal surfaces of heatexchange systemsmade of iron, steel, aluminum, brass, copper, lead, tin,. or alloys containing one .or more of theseor similar; metals, and which will leave the metal surfaces clean and corrosionresistant; to provide a novel acidic cleaning composition in dry or, solid state, which is stable in storage andis readily soluble in water and aqueous solutions; to provide a novel acidic com position-for cleaning metal surfaces, and which is emulsifiable with oil-and grease, in an acid state, and which inhibits or retards the corrosion by the acidicccmponent ofaluminum, copper, and alloys containing copper and/or tin and/or z1nc.. 1

Inits broadest scope the invention involves the preparation and use of a novel cleaning com- ,position which preferably is pro-parable in the acid phosphate; ahd oiall'c antl A? state of a dry or solid mixture, and which comprisesg 1)} an acidic agent capable of dissolving rustof loosening an removing scale and metallic oxide coatings from metal surfaces; (2) an organic compound of the type hereinafter described, capable of functioning as an emulsife ingagent for oils and greases in an acid, a neutr oranalZaline medium; and -(3) an agent which effectivelyinhibits or retards the macaw the said acidic agent upon. those portions 'of aheatexchange system made of aluminum, brass, cop; per, tin, lead, and alloys thereof.

Although any solid water-soluble acid, or a water-soluble compound capable upon hydrolysis of yielding an acid, or mixtures of such substances, may be used as the active cleaning agent, it is preferred to use a compound which is stable in the dry state and is readily miscible with the other solid ingredients in finely-divided form. One example of such agent is sodium bisulfate. How any other water-soluble solid acidic emastne' iaaeeaaerrmm w m which are other ac We w. u 1 ying agent, thre may be used a wide variety of organic compounds,

lixaminer i including the sulfonates and sulfate esters produced by the sulfonation or sulfation of various saturated and unsaturated organic compounds having six or more carbon atoms in their molecules, such as aliphatic and aromatic monohydrie and polyhydric alcohols, fatty acids, amines,

naphthenic acids, h*ydroxy fatty acids and esters derived therefrom; and salts derived from these sulfonates and sulfate esters by treatment with a base.

. Among emulsifying a ig form. .j

be mentioned fatty acid esters of polyhydrox'y aliphatic compounds and derivatives thereof sqich as diglycol oleate, diglycol stearate, and coridensa tion products of fatt acids with glvcerine or with derivatives of these hydroxy compounds, such as I ethylene glycol monoalkyl ether-s; nydroxyamm amines and derivatives thereof, such as the ethanolamine soaps, and sulfonates thereof, "and the condensation products of such amines with alkyle'nef oxides, halqhydrins and sulfonate's; 'alkyl "halides 'suohas cetylamine hydrochloride, ctyf'dit'lrylamine hydrochloride, and cetyItritYiyI ammem'um iodide; sulfonatcd suba'iiiides or carboiylic acids, such the s'odihrii s t of -the a'ln'iiioderivative of oleic acid and amino-ethane-suifonio acid;- amide of aliphati'c 'acidsulPates and sulfonates; benzene sulaci'd saltsa'hd esters, amides, and alkylated eefivative's thereof; -niiphthalene sulfonic "acid salts and esters, amides and alkylatedfderivatives thereof; phenol sune'nic a'ci'd salts and esters, anidessand alkylat'ed derivatives thereof; hapli-thol slflfoni'c acid Salts and esters, amides, ahd-alk'ylated derivatives therefiand cresolsulre'mc aeia saitaane esters-amides,- and alk'ylated derivatives 'tlireof.

products derived by the sulfonatien "or seamener saturatedbraneh'ed-chaih secondary alcohols having-eight to seventeen or more a'rwherein {A designates either 'hydrogeni or "the methylgroup -Rdesignates an alkyl groupcon taining'at least nine carbon atoms, preferchlorsulfonic ftures f feor'respond'in'g deriivati'ves of alkylated benzene-the components of the respective mixtures having a composition corresponding to the respective formulae ,w e ei ie a we e ee e w e e ee et e e ee mi m groups inthe of these alkylated oompounds Lprfez: fly average around foli rteen-carbon atoms.

S'uch products may betnade for -example,-by c'l'ilori'nating under pressure the lkefosenelfracnon of apaxafiin mineral .oil, resultant, of alkyl chlorides with. phenol inth lpresence o'fai'nc chloride as a-con'deiis or catalyst, suilfonating'the resultant aneualtedphe'nol i'n well-known manner with a suI'fonatl'ng agent as :rummg sulfuric acid or a waters o'luble "base. ich as I hydroxide or .car- Bonate, the "eliminated product jithus, obtained. The original k'fos'he fr'action a specific 'gravitybetween D178 and 10.80; whereas the chIorihftedjkerqsenejmaji'have a'spe'cfficgravit between 0191'anaj'0e25; i V i v "if desired, the ke osene rraction'rnay befra'ctioriateditoisepar 'te it'into'sele'c'tsd" iractionsrthe geietedination lialoghfitii lfnfthe' manner indicated; am the ha-lbginatefdprodiict mrtiier treated to .n odn utiie jsaltbf'theisulfonated defivative'tnereof; p, r

1' feiabovam entionen'sodimns nronates oralkyi'ate d 1111611914 3 nlllit'tii'e'sfof said "sulfonatswm m r it nv meneemn e 'd s m d er matter as triesodium sulfonate "of tetrauenvl phen pl -are solids, solublein water, and contain around 'equal j'parts of the said sulfonate and of sodidm' sulfate. fInjan acid solutionitlalsogives some corr'o ipn "re istance i to non-ferrous metals dime type, meritmnedjabqve; This protection, when aflomeuim eonneetion with the use or acid so ut ons? als ii xi alnmejp msfi her i afterdesci'ibd, isgreatestwnen me-ratio offlthe sodium sulfonatejjof;tetradecyl .phenol to the phosphate group is two .or"three 'to' one. some 'pr nuctio isi afioriied even outside these limits. Byimalntaifiiirgthe ratio of said suifohate to "the lphosphate groupjwithin the limits indicatea sobstannauy'nu electrolytic corrosion ot flb ass surtacesexposedj tothe' liquid occurs. 7

Due procedure r o r producing, awater-soluble emanate-(transmi ter: benzene isas "follows: ,rommerarfl I kerosene fraction or a paraiiin nase'mmerai-on is 'rrraetionateuy-and the fraction containing the hydrocarbons within the fifi'fig'fromTfictanei tciihxadcane ls -ehro'rmatea mf ninofires ofamfl"cmorittesftnus rormed'are condensed f with jefizenein' the? presence "of 'zinc Chloride or 'Jas-a'eataIysUand r52. comeosmows. ii 4 7 the resultant mixtures of alkylated benzenes are sulfonated'in the usual manner with, concen-, trated sulfuric acid or, chlorsulfonic acid. The sulfonation product is then neutralized by means of a water-soluble base, such; as sodium hydroxide or carbonate, ammonia or an amine. A pro cedure of this type is disclosed in United States Patent 2,161,174 of L. P. Kyrides. -,It is well known that any acidic reagent capable of readilyremoving scale, rust and other oxides from ferrous, and non-ferrous, metal sur faces must attack such surfaces. Indeed, inhibitors effective for protecting ferrous metal from undue corrosion frequentlydo, notinhibit' the attack of cooling system parts made of; alumi-, mum and other non-ferrous metals. It now has been discovered that the presence inzthe composition of a small amountof a. water-. soluble phosphate such as the ammoniumand alkali metal phosphates, in conjunction with the said emulsifying agent, which also possesses some corrosion inhibiting action, affords splendid pro-. tection for, non-ferrous. metal surfaces. A basicphosphate, such as secondary ammonium phos: phate, has been found especially effective for inhibiting. the action of the acidic component. upon aluminum, aluminum, alloys, and copperand copper alloys. A portion of the phosphate, if desired, may be replaced with other substances.- having a somewhat similar. action,,such as, a water-soluble cyanate; or Phosphine G. N.," the latter of which is a.yellow-brown dye readily, available on the market under this trade name.

When using an acidic salt containing substantial amounts of chlorides or nitrates, it-is. desirable to increase-somewhat the amount ofinhibitorused, since theef'nciency of the lattermay be somewhat reduced inthe presence of these salts. 1 A

The components of the cleaning composition preferably are mixed in the dry state. Alter-- natively, the composition can be prepared in the are stable in storage, and

are readily and safely transported.

A mixture containing 84.5% hy weight of:

finely-divided sodium bisulfate, about 6% of the aforesaid finely-divided sodium sulfonate derivative of tetradecyl phenol, about %v ofsodium;

sulfate, and 4.2% of dibasic ammonium phose phate provides these solid ingredients in proportions such that, when. the mixture is dissolved in water to yield dilute solutions containing the acidic ingredient within the range of concentra: tions hereinafter specified, the other ingredients will be present in amounts ,sufitlcient to insure their functioning in the manner described.

In utilizing the invention, preferably sufficient of the composition is mixed with water,. or its equivalent, to provide a liquid having an effective free acid concentration of from 0.1% to A concentration of from .01% to 1% of the water-soluble emulsifying agent ordinarily, is required, depending largelyupon the amount and nature of the oil and/or grease that must. be

emulsified.

The amount of the phosphate or other inhib-' itor depends upon the presence or absence of non-ferrous metals readily attackable by the acid solutions. Generally around .15% of the inhibitor in the-said liquid is'sufiicient, though more or less than this amount can be employed. The

phosphate ion, in concentrations of from .05%'

Cross Reference to 0.5% or more of the solution, effectively inhioe its. corrosion of. the non-ferrous'metals hereinbeforenamed. In use, a solution of the cleaning composition in water, alcohol, orother suitable vehicle, is con-. tacted-with-the metal surfaces to be. cleaned, preferably in the heated state. Thus, in cleaning the cooling system of an internal combustion engine, an aqueous solution of the said composi-= tionv is circulated through the coolingv system while; running the engine, thus heating the solu--.

tion .to-around- F. After .suchoperation, which may last for from fifteen minutes to several hours or more,the cleaning solution is withdrawn, and the system is flushed and re-.- filled with clean hot water once or twice.

1 Preferably the water used for the first flushing contains a neutralizing agentsuch as sodium carbonate in amount sumcient to neutralize alltraces of residual acidic substance. This treatment with neutralizing agent particularly is desirable when the cooling system subsequently is to be filled withan antifreeze compound or other liquid containing an alkaline component.

The followingexamples serve to. illustrate the invention: I

- -Example1 1'.

An aqueous solution containing 3% sodium bisulfate, 0.4% of the aforesaid sodium sulfonate derivative of tetradecyl phenol (containing approximately 44% of the said sulfonate; 55.5% of sodium sulfate, and 0.5% of zinc sulfate), and 0.15% of dibasic ammonium phosphate, was cir culated' at a temperature of around 175 F. through the cooling system of aninternal combustion engine for about one hour; The solution then was withdrawn; and the system was flushed with a dilute aqueous solution of sodium carbonate' slightly in excess of that required to neu-- tralize the residual acid present. This solution thenwas withdrawn and the system was flushed with clean water. This assisted in removing loose rust particles and in rinsing out dissolved iron oxide that had been reprecipitated by-the carbonate. The 'metal parts of the system were effectively cleaned of scale, rust, and oily materials by the treatment.

-An aqueous solution containing 3% of sodium bisulfate; 0.25% of the sodium salt of the sulfate ester of tetradecanoll, (produced in the manner described in United 1 States Patent 2,088,014 of J. N. Wickert and B. T. Freure) and about 0.15% of secondary ammonium phosphate;-

was prepared by dissolving in water a mixture of 480 parts of sodium bisulfate, 64 parts of the said sodium salt, and 24 parts of secondary ammonium phosphateall parts by weight. This solution was circulated at a temperature around 175 F. through a radiator, in the general manner described in Example 1, and was then withdrawn and the radiator flushed in the manner described in that example. The metal parts were efiectively cleaned of rust, scale, and oily materials. Similar solutions wherein the said emulsifying agent was replaced with an equal quantity of sodiumoctyl sulfate were somewhat less efiective for removing grease from the radiator, and for assisting the inhibitor to protect non-ferrous surfaces from corrosion.

.lar to that described in Example 1, with the ex-= Examiner *oeption-thet-0A%-ol the sodium saltof monoculfonated monoalkylated benzene, wherein =fl1e llkyl group contained around fourteen oaflmn atoms, was substituted for the-sodium sulfonate u! betradecyl phenol set forth in that example. This aqueous solution was simulated through the cooling system in the mpact infllcdted h Example 1. substanuauy "them results wsie "This application is a 'continuation-ln-part ot my copen'cllng application, fiserlal No. 33,842, In! Cleaning composition and fo'r itsuse, filetl'MayB, 936. The invention is susceptible of modification within the-scope of meappendefi claims;- 3 V lclaim:

Y e 1. An acidic cleaning composition thaws-stable in solid form, and adapted in aqueous solution to remove scale, oxide impurities, grease and oil from ferrous and nonderrous metal surfaces, while inhibiting acid attack -upon surfaces of aluminum, brass, copper, tin and lead, which composition comprises a solid alkali metal salt of an inorganic sold adapted in aqueous solution tohydrolyzeand yield a freehold; *a solid watersoluble salt of a compound selected hem the group consisting of *the suli'onation products of alkylated phenols-and oresols .having -.between nine and sixteen; carbon atoms in the align-group,

the sulfonation products of -.alkvlated benzene having between 'nine and sixteen carbon atoms in the alkyl group, andthe sulfonatlon and sulfation products of monohydric eliphaticaloohoks having'betweeneight and seventeen carbon atoms in the molecule; and a small amount f .a solid water-soluble phosphate corrosion inhibitor.

.2 A- cleaning composition that isstablein solid form and isacidipin aqueous solution, said coinnosition being adapted in aqueous solution to remove scale, oxide impurities,,grease and {oil trom ffQII'OllS and non-ferrous metal surfaces. while inhibiting acid attack upon surfaces of alumin m, brass, copper, tin and lead-11s said solution, which composition comprises a nuxture in. finely-divided solid form of a major portien of .an alkali metal salt or an inorganic acid adepted in aqueous solution to yields. free acid;a=. water-soluble salt of a. sulfonated derivative of a compound selected from the-group consisting of the alkylated phenols and alkylated-lcresols wherein the alkyl zgzoupeontainsebctween' nine and sixteen carbon atoms, -the=alkylated benzenes wherein the .e'lkltl group vcontains "between-nine and sixteen. carbon atoms, and the aliphatic monohydric ;fl-lc0hols having between eight ,and seventeenearbon atoms; and a small amount :of a water-sohxble phosphate eficctively inhibiting the corrosion of non-ferrous metals by omantic: oussolution-of saicl-mmpositi0n.-'i.- l.- 2 cleaning, composition that is stable iin solid form, and adapted inwaqueo'us osolntionzto remove scale, :oxide impurities, grease and :oil from ferrous and non-ferrous metalsuriacee, while inhibiting laoid attack upon surfaces of alimilnumfbrass, copper, fin'and ieadfiwhioh composition comprises-a. finely-divided solid-mixture ofo major portion of an alkali metal inorganlc salt adapted infa'queous solution to h?- drolyze and yield a free acid; a Waber-soluble saltof a sulfo nated derivative oi ,an allgylateid phenol having between nine andsixteen carbon atoms in the alkyl group; and a small amount of a water-soluble phosphate 'efiectively inhibiting the corrosion of non-.ferrousmetals hysaid oom-.

position in aqueous solution; said composition substantially-Eddie in aqueous solution. 4. A-cleamng composition that is stable insolld 50m. and ndapted ail-aqueous solution to move scale, oxide impurltim, groaseend oil from far-- T0138 and non-ferrous metal surfaces, while in- =hioiting acid attack upon aluminum, brass, copper, {in und lead, which composition comprises a mixture in finely-*divltled solid form of -e; major erucm'or an alkali metal salt of an inorganic acid adapted in aqueous solution *to yield a. free-acid; a water-soluble salt'oi asul- 'fonated derivative of on elkylated benzene hav- =ing between nine "and sixteen carbon atoms in the alkyl group; and-a Small amount-of a, watersoluble phosphate effectively inhibiting the cor s-osion-of non-lemons metals by an aqueous solution of said composi'tion; said composition-being substantially acldic ln aqueoussolution.

5. -A cleaning composition in solid form, adopted in aqueous solution to remove scale; oxidelmgrease and cilia-om ferrous and nonferrous metalsurfam while inhibiting'acid atme: upon surfaces of aluminum, brass, copper, tin and lead bysald solution,=whioh composition comprises a, major portion of a water-soluble alkali metal zbwulfate adapted .in aqueous solution to release a free acid; a water-soluble salt of osulfonated derivative of a compound selected from the group consisting-of the aliphatic-monomum alcohols having between eieht and seventeen carbon atoms'thealkylamd phenols and alkylatedcresols wherein the alkyl group contains between nine andsixteen oarbonatomsend the alkylated benzenes wherein the alkyl group contains between nine and sixteen carbon atoms; and a small amount of a solid water-soluble phosphate elfectively inhibiting the corrosion of aluminum and other non-ferrous metals by an aqueous solution of the-composition,suid oompesltion being acidic inaqueous solution. a

-' 6. A cleaning composition that is stable-in solid form and is acidic in aqueous-solution, and adaptedin 'solution'ln water to remove scale, oxide 1mpurities, grease and'oll *from ferrous and non- !rrous metal surfaces, while inhibiting acid attack upon surfaces of aluminum, brass, copper, tin and lead, which composition-comprises; mixsure-of solid components comprising, by weight, about85% of a water-soluble bisulfote adapted in aqueous solutionto yield-o 'free acid, ebout'6% or swatch-soluble salt of asulfonated-derlvatlve of a-compound selected from the group'consista lng-ofthealkylated-phenols and olkylated cresols wherein the alkyl group contains between nine andsixteen carbon atomsQthealkylsted benzenes wherein :the 'elkyl group contains between nine and sixteen casbon atonzs, and the aliphatic monohydricolcohols having between eight and seventeen carbon atoms; -and-about 4%-of a water-soluble phosphate-efieotive'ly inhibiting the corrosion cinch-ferrous metals -by an'aqueous solution ofsaidcomposition, the balaneebelng a, water soiuble sulfate. T 7. e l cleaning-composltion'that is stable insolid form bnd 'isacidic in aqueous solution, and adopted in aqueous solution toremove scale, oxide-impurities, grease and oil from ferrous and monfermus metal surfaces while .inhibitingsdd attack upon surfaces of aluminum, brassncopper, tin andi'l ead; which composition comprises'a mixture-of solid components comprising by weight about 1.85% of 11 wateresoluble .bisulfate adapted ingaqucous solution to, yield: a -f-ree=.acid,- a.b0ut- 6 of a water-soluble salt-of -a:sulfonated derivative 252 comeesmeNs. l a

Cross Reference aminer of an alkylated phenol having between nine and sixteen carbon atoms in the alkyl group, and about 4% of dibasic ammonium phosphate, the balance being a water-soluble sulfate.

8. A cleaning composition that is stable in solid form and is acidic in aqueous solution, and adapted in aqueous solution to remove scale. oxide impurities, grease and oil from ferrous and non-ferrous metal surfaces, While inhibiting acid attack upon surfaces of aluminum, brass, copper, tin and lead, which composition comprises a mixture of solid components comprising, by weight, about 85% of a water-soluble bisulfate adapted in aqueous solution to yield a free acid, about 6% of a water-soluble salt of a sulfonated derivative of an alkylated benzene having between nine and sixteen carbon atoms in the alkyl group, and about 4% of dibasic ammonium phosphate, the balance being a water-soluble sulfate.

9. An acidic cleaning composition adapted to remove scale, oxide impurities, grease and oil from ferrous and non-ferrous metal surfaces, while inhibiting acid attack upon surfaces of aluminum, brass, copper, tin and lead, which composition comprises an aqueous solution containing approximately from 0.1% to 10% of a free inorganic acid; from 0.01% to 1% of a watersoluble salt of a sulfonate-d derivative of a compound selected from the group consisting of the aliphatic monohydric alcohols having between eight and seventeen carbon atoms, the alkylated phenols and alkylated cresols wherein the alkyl group contains between nine and sixteen carbon atoms, and the alkylated benzenes wherein the alkyl group contains between nine and sixteen carbon atoms; and a water-soluble phosphate in amount suflicient to provide in said solution a phosphate ion concentration of between 0.05% and 0.5%; and water.

10. The method of cleaning metal surfaces, portions of which are formed of non-ferrous met als such as aluminum, brass, copper, tin and lead, while inhibiting the corrosion of said metals, which comprises applying to said metal surfaces, while heating the same, an acidic aqueous solution formed by mixing with water an alkali metal bisulfate, a water-soluble organic sulfonation product, and secondary ammonium phosphate; said water-soluble sulfonation product essentially comprising a solid water-soluble salt of a compound selected from the group consisting of the sulfonation products of alkylated phenols and cresols having between nine and sixteen carbon atoms in the alkyl group, the sulfonation products of alkylated benzene having between nine and sixteen carbon atoms in the alkyl group, and the sulfonation and sulfation products of monohydric aliphatic alcohols having between eight and seventeen carbon atoms in the molecule; the said solution having an effective free acid concentration of between 0.1% and 10%, from 0.01% to 1% of said water-soluble sulfonation product, and a phosphate group concentration of between 0.05% and 0.5%; thereafter withdrawing said solution from contact with the cleaned surfaces, and neutralizing at least the major part of any residual solution in contact with said surfaces' TIMOTHY J. COLEMAN. 

